Buying Land in Pima County, Arizona

A real, detailed zoning code -- and rural zones built for large desert lots

Pima County Code Title 18 is a genuine, mapped zoning ordinance covering the unincorporated county, not a nominal or rarely-enforced one. The Comprehensive Plan -- first adopted in 1992, revised in 2001, and most recently updated in 2015 -- sets the planned land-use framework that Title 18's zoning districts and the county's rezoning process are legally required to conform to; the Board of Supervisors acts on rezonings as a legislative matter. Development Services' Planning Division administers day-to-day zoning questions, conditional use permits, variance requests, and zoning verification letters for a specific parcel.

For rural land specifically, the code includes large-lot residential zones built around desert ranch-style living: the RH (Rural Homestead) zone, with a minimum lot size around 180,000 square feet (roughly 4.1 acres), and the SR (Suburban Ranch) zone, at roughly 3.3 acres minimum, both intended for single-family residences with room for horses, agriculture, and related accessory uses. These are meaningfully different from urban and suburban residential zones closer to Tucson, so a parcel's specific zone -- not just its general location -- determines what you can actually build and keep on it. Confirm the zone, and any recorded conditions or overlay districts, directly with Development Services before relying on a listing's description.

Tucson's gravity: a narrow but real rural land niche, not a countywide rangeland market

Pima County covers roughly 9,189 square miles, but its population of about 1.06 million people -- Arizona's second-largest county by population -- is overwhelmingly concentrated in and immediately around the City of Tucson and its incorporated suburbs (Marana, Oro Valley, Sahuarita, South Tucson). That's a fundamentally different pattern than most of rural Arizona: this isn't a county where raw land is spread evenly across open rangeland with a small county seat. If you're looking at unincorporated land here, you're generally looking at one of a few specific outlying pockets -- Avra Valley and Three Points/Robles Junction west of Tucson, the Green Valley/Sahuarita corridor to the south (itself increasingly suburbanized), or the more remote Ajo area in the county's western reaches.

That concentration cuts both ways for a buyer. It means genuine raw desert land at rural prices does still exist here, but it's a narrower niche than in a county where unincorporated rural land is the norm -- and land closer to Tucson's growing edge carries real development and rezoning pressure that more remote parcels don't. Confirm which pattern applies to a specific parcel: is it isolated desert land likely to stay that way, or land in the path of Tucson-area suburban growth where the Comprehensive Plan's future land-use designation (not just its current zoning) matters for long-term value.

Flood control is a real, funded regional authority here -- not just a FEMA map

Pima County Regional Flood Control District, created as a special taxing district, runs a substantial, active floodplain management program: more than 230,000 acres of federally-mapped 100-year flood hazard area sit along over 130 miles of major watercourses in the eastern part of the county, and any parcel near a wash may need its own Floodplain Use Permit -- separate from zoning and building permits -- before construction, septic, or grading. The District also regulates its own broader "regulatory floodplain" and a mapped Erosion Hazard Setback that reach further than FEMA's flood maps alone; see the dedicated flood-zones page below for the specifics.

Two trust-land communities sit outside the county's zoning and flood-control jurisdiction

The Tohono O'odham Nation's San Xavier District (71,095 acres immediately south of Tucson) and the Pascua Yaqui Tribe's New Pascua and Old Pascua communities are federal trust land, entirely outside Pima County's Title 18 zoning code, Development Services permitting, and the Regional Flood Control District's authority. See the dedicated tribal-trust-land-status page below for how leasing and land status actually work on each.